Incidence, predictors, and risk stratification of the no-reflow phenomenon during primary percutaneous coronary intervention in st-elevation myocardial infarction: A Prospective Observational Study
DOI:
https://doi.org/10.58889/PJCVI.5.2.65.73Keywords:
Diabetes Mellitus, Myocardial Infarction, No-Reflow Phenomenon, Percutaneous Coronary Intervention, Risk Factors, Time-to-TreatmentAbstract
Background: To determine the incidence, identify independent predictors, and develop a clinically applicable risk stratification model for angiographic no-reflow in patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI).
Methodology: All consecutive adult patients (≥18 years) presenting with STEMI within 24 hours of symptom onset and undergoing primary PCI were enrolled. Patients with prior myocardial infarction, recent revascularization, cardiogenic shock, or severe renal failure were excluded. Clinical, demographic, and angiographic variables were recorded using standardized definitions. No-reflow was defined as Thrombolysis in Myocardial Infarction (TIMI) flow grade ≤2 or TIMI grade 3 with myocardial blush grade ≤1 after final PCI. Independent predictors were identified using multivariate logistic regression, and a weighted risk score was derived from β-coefficients.
Results: Among 650 patients (mean age 56.6 ± 13.3 years; 18% females), no-reflow occurred in 159 patients (24.5%). Independent predictors included age ≥60 years (adjusted odds ratio [OR] 13.82, 95% confidence interval [CI] 8.08–23.65), total ischemic time ≥6 hours (OR 4.75, 95% CI 2.88–7.83), high thrombus burden (OR 4.36, 95% CI 2.63–7.23), anterior myocardial infarction (OR 2.86, 95% CI 1.75–4.67), and diabetes mellitus (OR 2.29, 95% CI 1.39–3.77). The model demonstrated excellent discrimination (area under the curve [AUC] 0.896) and good calibration (Hosmer-Lemeshow p=0.49). Risk stratification showed a marked gradient in no-reflow rates from 1.8% in low-risk to 68.2% in very high-risk groups.
Conclusion: The no-reflow phenomenon complicates approximately one-quarter of primary PCI procedures in STEMI. A simple five-parameter risk score based on routinely available variables provides robust risk stratification and may facilitate targeted preventive strategies in high-risk patients.
